[PATCH v2 3/7] recipes-kernel/linux: make KERNEL_DEFCONFIG support in-tree defconfigs

[Cedric Hombourger <Cedric_Hombourger@mentor.com>]

The recipe expected the specified KERNEL_DEFCONFIG to be provided as a
SRC_URI while the kernel already provides many useful defconfigs. The
recipe will now check if the specified configuration can be found in
WORKDIR. If it is found, it will then be used via "make olddefconfig"
as before. It will otherwise assume that it is an in-tree defconfig
and attempt a "make foobar_defconfig" (where foobar_defconfig is the
user-provided KERNEL_DEFCONFIG setting). To support this change, a
KERNEL_CONFIG_TARGET variable is passed to the build-kernel.sh script
via the environment.

Signed-off-by: Cedric Hombourger <Cedric_Hombourger@mentor.com>
---
 meta/recipes-kernel/linux/files/build-kernel.sh | 6 +-----
 meta/recipes-kernel/linux/linux-custom.inc      | 9 ++++++++-
 2 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/meta/recipes-kernel/linux/files/build-kernel.sh b/meta/recipes-kernel/linux/files/build-kernel.sh
index b46cefa..386e58b 100644
--- a/meta/recipes-kernel/linux/files/build-kernel.sh
+++ b/meta/recipes-kernel/linux/files/build-kernel.sh
@@ -36,11 +36,7 @@ REPACK_DIR="$1/../repack"
 REPACK_LINUX_IMAGE_DIR="${REPACK_DIR}/linux-image"
 REPACK_LINUX_HEADERS_DIR="${REPACK_DIR}/linux-headers"
 
-if [ -e .config ]; then
-	make olddefconfig
-else
-	make defconfig
-fi
+make ${KERNEL_CONFIG_TARGET} || exit ${?}
 
 KV=$( make -s kernelrelease )
 if [ "${KV}" != "${PV}" ]; then
diff --git a/meta/recipes-kernel/linux/linux-custom.inc b/meta/recipes-kernel/linux/linux-custom.inc
index 5a34dd1..0f7633a 100644
--- a/meta/recipes-kernel/linux/linux-custom.inc
+++ b/meta/recipes-kernel/linux/linux-custom.inc
@@ -61,8 +61,14 @@ addtask devshell after do_install_builddeps
 
 dpkg_runbuild() {
 	chmod +x ${WORKDIR}/build-kernel.sh
+	KERNEL_CONFIG_TARGET="${KERNEL_DEFCONFIG}"
 	if [ -n "${KERNEL_DEFCONFIG}" ]; then
-		cp ${WORKDIR}/${KERNEL_DEFCONFIG} ${S}/.config
+		if [ -e "${WORKDIR}/${KERNEL_DEFCONFIG}" ]; then
+			cp ${WORKDIR}/${KERNEL_DEFCONFIG} ${S}/.config
+			KERNEL_CONFIG_TARGET="olddefconfig"
+		fi
+	else
+		KERNEL_CONFIG_TARGET="defconfig"
 	fi
 
 	E="${@ bb.utils.export_proxies(d)}"
@@ -71,6 +77,7 @@ dpkg_runbuild() {
 	export KERNEL_NAME=${KERNEL_NAME_PROVIDED}
 
 	export KBUILD_DEPENDS="${KBUILD_DEPENDS}"
+	export KERNEL_CONFIG_TARGET
 	export KERNEL_DEBIAN_DEPENDS="${KERNEL_DEBIAN_DEPENDS}"
 	export KERNEL_FILE="${KERNEL_FILE}"
 	export KERNEL_HEADERS_DEBIAN_DEPENDS="${KERNEL_HEADERS_DEBIAN_DEPENDS}"
-- 
2.20.1